Finished asphalt path at Castletown Close access point onto the Transpennine Trail, with a gravel-filled drainage mat apron at the verge

Case Study

Liverpool Live Labs: Transpennine Trail

A Live Labs 2 demonstration at Castletown Close, combining Rosehill Drainage Mats, Stackers and Grip Strip to keep an access point onto the Transpennine Trail completely puddle-free.

Project Overview

Liverpool City Council's Live Labs 2 programme has chosen Castletown Close — an access point onto the Transpennine Trail — as a demonstration site for an integrated Rosehill drainage system. Delivered with DOWHIGH Limited, the scheme combines Drainage Mats, Stackers and Grip Strip for the first time, replacing a persistently flooded walkway and an adjacent waterlogged patch of ground with a modular, recycled-material installation that routes both catchments into an existing on-site drain.

The Challenge

Chronic surface-water pooling on the access path, making it unusable in wet weather
An adjacent patch of ground that had become standing water — the most flooded part of the site
Environmentally sensitive woodland setting that ruled out deep trenching and new pipework
Key active-travel route into the Transpennine Trail that needed to stay open for residents, cyclists and commuters
An existing drain was already on site — but it was not capturing either catchment

The Solution

A 5m × 6m Drainage Mat bed laid over the worst-flooded ground — replacing standing water with a permeable, trafficable surface
Stackers running from the mat bed across to the existing drain, carrying collected water out and bridging the depth between the mat level and the drain invert
A fan of Grip Strip spurs collecting surface water off the new asphalt path and feeding it into the same existing drain
Modular, recycled-material build installed quickly on site with no deep trenching — preserving the woodland setting
Sealed asphalt wearing course finished with a visible gravel-filled mat apron at the path-to-verge transition

“The new Rosehill Group drainage system installed by DOWHIGH is doing exactly what it should — the pedestrian walkway is now completely puddle-free.”

— Liverpool Live Labs 2

Results

Walkway completely puddle-free on commissioning, and again at post-commissioning review weeks later
Gravel grid continuing to drain any residual water at the path-to-verge apron
Previously flooded ground now a stable, usable permeable surface
Both catchments safely routed into the existing on-site drain — no new outfall required
System performing exactly as intended, with ongoing monitoring planned over the coming months

Why It Matters

Castletown Close shows how Rosehill's modular system can be adapted to plug into existing drainage infrastructure rather than requiring new outfalls — a practical approach for flood-prone paths in built-up and environmentally sensitive settings. As a Live Labs 2 demonstration location, the methodology is intended to replicate across Liverpool, and it is the first Rosehill installation to combine Drainage Mats, Stackers and Grip Strip as an integrated system rather than three separate products.